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Thank you for purchasing this 2-Port RS232/422/485 Combo
Serial to USB Adapter. It is an intelligent expansion module that
connects to a PC or server via the Universal Serial Bus (USB),
providing high-speed serial connectivity. The serial ports are
fully compatible with RS232/422/485 standard by the bundled
virtual COM port drivers. With its rigid metal case and USB Screw
Lock Mechanism, it is an ideal solution for most critical
applications.
2-Port RS232/422/485 Combo Serial to USB2.0
Adapter (w/ Metal Case and Screw Lock
Mechanism)
Installation Guide
1. Introduction
Port 1
Port 2
2. Connector Layout
Port 1 Mode LEDs
Port 2 Mode LEDs
Power LED
Port 1 TX/RX
Activity LEDs
Port 2 TX/RX
Activity LEDs
Rear Panel
Screw Lock
USB Cable
2-Port RS232/422/485 Combo Serial to USB2.0 Adapter
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Features:
Provides 2 RS232/422/485 Serial Ports over USB Port
Provides 2 DSUB-9 Connectors
Supports USB2.0 High Speed (480Mbps) Data Rate
Supports USB Screw Lock Mechanism Enhances Reliability
Baud Rate from 300 bps to 921.6Kbps
Supports 7,8 Data Bits
Odd, Even, Mark, Space, or None parity mode
Supports 1, or 2 Stop Bits
Supports USB Bus Power
Optional Model Supports 2,500Vrms Isolation and 15KV ESD
Protection
Supports Win98, Me, XP, CE, 2K, 2K3, Vista and Windows 7
There are two 4-pin DIP switches on the back side of the box for Port 1
and Ports 2. Each of them has 4 switch pins on it. Pin 1 to 2 (marked as
M1 and M0) were used to set the RS232, RS422 or RS485 modes. The Pin
3 and 4 (marked as TERM ON) are used to Enable(ON) or Disable(OFF)
the termination resistors for RS422/485 modes.
Port 1, 2 DIP Switches:
Mode Settings:
Switch Settings
Description
RS485 2-wire mode
(Default)
3. Mode Switch Settings
ON
1 2 3 4
M1
M0
TERM ON
TERM ON
RS422/485
mode
selector
Termination
resistors’
enabler
ON
1 2 3 4
M1
M0
TERM ON
TERM ON
2-Port RS232/422/485 Combo Serial to USB2.0 Adapter
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RS485 4-wire mode
RS422 mode
RS232 mode
(Note: Both Pin 3 and 4 have to
be set at OFF to work in RS232
Mode)
The image above shows how the TERM ON pins modifies the circuit
The TERM ON pins can apply 1K pull-up & pull-down resistors
ON
1 2 3 4
M1
M0
TERM ON
TERM ON
ON
1 2 3 4
M1
M0
TERM ON
TERM ON
ON
1 2 3 4
M1
M0
TERM ON
TERM ON
2-Port RS232/422/485 Combo Serial to USB2.0 Adapter
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The RS-232 Multi Serial Adapter can be hot-plugged to the USB
port of your computer due to the specifications of USB. It
supports the following operating systems. The drivers are
shipped in the following folder on the supplied driver CD.
1. Driver Locations on the CD
These instructions are for installing the drivers from the CD
supplied with the product. If you are installing drivers for Win98,
ME, 2000 or XP, when prompted for the location of the drivers,
specify your CD-ROM drive and the locations according to the
following table:
2. Installing Serial Port Drivers for Win98, ME, 2000,XP
Insert the Driver CD supplied with the Adapter
Connect the USB cable, the “Add New Hardware
Wizard” appears. Click Next.
Select “Search for the best driver for your device”
and click Next.
4. Installing Drivers
Linux
Mac OS 9.x, 8.x
Mac OS X
Windows 2000, XP,
Server 2003
Windows 98, 98SE, ME
Windows CE for ARM
Windows CE for ix86
Windows XP, 64bit
2-Port RS232/422/485 Combo Serial to USB2.0 Adapter
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Assume the CD-ROM is drive E:, select “Specify a
location” and browse to the following folder:
E:\USB_to_IO\FTDI\Win2000_XP_2003
E:\USB_to_IO\FTDI\Win98_ME
Click Next. Windows will then copy the driver files.
Click Finish to complete the driver installation.
After installing the drivers, Windows will detect the
new COM ports and will begin to initialize them. Your
new COM ports, numbered sequentially following the
existing ports in your system, and they are now ready!
DB9(Male) to DB9(Male) Wiring
5. RS232 Mode Male DB9 Pin Assignments and
For Win2000,
XP or Server
3003,
For Win98, ME
1 5
6 9
9 Pins Signal
1 DCD
2 RXD
3 TXD
4 DTR
5 GND
6 DSR
7 RTS
8 CTS
9 RI
DB9(USB Adapter) DB9(Serial Device)
1 DCD 1 DCD
2 RXD 2 RXD
3 TXD 3 TXD
4 DTR 4 DTR
5 GND 5 GND
6 DSR 6 DSR
7 RTS 7 RTS
8 CTS 8 CTS
2-Port RS232/422/485 Combo Serial to USB2.0 Adapter
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DB9-Male Pin Assignment:
RS422 Cable Wiring:
RS485 (2-wire) Cable Wiring:
Power requirements: 5V DC, 385mA (max)
Operating temp.: 0 to 55°C (32 to 131°F)
Operating humidity: 5 to 95% RH
5. Environmental Specifications
6. RS422/485 Modes Male DB9 Pin Assignments and
DB9 (RS422 to USB Cable)
1 TXD-
2 TXD+
3 RXD+
4 RXD-
5 GND
(RS422 Device)
1 TXD-
2 TXD+
3 RXD+
4 RXD-
5 GND
NC = No connection
1 5
6 9
9 Pins Signal
1 TXD- (DATA-)
2 TXD+ (DATA+)
3 RXD+
4 RXD-
5 GND
6 NC
7 NC
8 NC
9 NC
DB9 (485 to USB Cable)
1 DATA-
2 DATA+
3 NC
4 NC
5 GND
(RS485 Device)
1 DATA-
2 DATA+
3 NC
4 NC
5 GND
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